A conventional apparatus for preventing reverse rotation of a spinning reel is generally provided by a click gear installed inside a rotor of the spinning reel as described below.
As illustrated in FIG. 8, Korean Utility Model Publication No. 94-7711, which was assigned to Taiwa Seiko Corporation, discloses an apparatus for preventing reverse rotation of a spinning reel. The apparatus comprises an axis 6 integrally formed on a stopper click 4 coupled with a reverse click gear 3 inside a convexed portion of a rotor (not illustrated in the drawing), and an operative piece of the stopper click 4, which is operated by an actuating arm (not illustrated in the drawings) while journalling the axis 6 on the front of a main body 5 of the reel.
An operative body 7 is integrally installed at the axis 6 of the main body 5 of the reel. The operative piece 7 is operated by a cam portion of the actuating arm having a lever 8 supported inside the main body 5 of the reel. A normal press type spring 11 is installed on the stopper click 4 so as to engage the stopper click is with the click gear 3 for preventing reverse rotation.
According to the construction of the conventional apparatus for preventing reverse rotation of the spinning wheel as described above, if the lever 8 is moved toward the left side by the manipulating arms and thus the stopper click 4 is supported in a state of engaging the stopper click 4 with the click gear 4 for preventing reverse rotation, the rotor can be rotated in the clockwise direction but not in the counterclockwise direction due to the engaged state of the stopper click 4 and the click gear 3. Meanwhile, if the lever 8 is moved toward the right side by the actuating arm so that the stopper click 4 is in a state of disengagement separating the stopper click 4 from the click gear 3, the rotor can be freely rotated in either direction.
However, the conventional apparatus for preventing reverse rotation has a problem that the rotor slips when preventing reverse rotation. Therefore, it is a general practice to maximize gear tooth portion to ensure the engaged state of the stopper click 4 and the click gear 4. The number of gear teeth reduces in inverse proportion to the size of the gear tooth section, and reduction of the number of the gear teeth enlarges the angle of the guidance to reverse rotation. This disables a prompt prevention of the reverse rotation. Moreover, as illustrated in FIG. 8, if a stopper click is positioned on the floor of the gear 3, and the lever 8 is moved toward the right side for the purpose of preventing the reverse rotation, the rotor slips off the same length as the gear tooth portion until the end portion of the click 3 reaches the valley of the gear tooth portion. Accordingly, the conventional apparatus for preventing reverse rotation has a drawback of not fully guaranteeing an instantaneous braking.
Meanwhile, Japanese Utility Model Laid-Open No. 64-38963 discloses an apparatus for preventing reverse rotation which comprises a uni-directional bearing fitted around the internal circumference of a latch wheel, and a roller of the uni-directional bearing fitted around the external circumference of a bushing of a rotating axis.
However, the above apparatus has a drawback in that the circumferential velocity of the roller contacting surface decreases due to the small diameter of the bushing of the rotating axis, into which the uni-directional bearing roller is fitted. This creates a problem of not fully guaranteeing an instantaneous braking. Also, a load is partially put on the abutting surface of each component when preventing reverse rotation, thereby resulting in a possible deformation and a low durability of the roller.
The conventional bearing has no on/off switching function, and operates in uni-direction, thereby posing a problem of additionally installing a separate apparatus around the periphery of the unidirectional bearing. For instance, the apparatus disclosed in Japanese Patent Laid-Open No. 64-38963 has a construction in which a gear is fitted into the external periphery of the uni-directional bearing to prevent its rotation, while the gear teeth are detachably engaged with the gear. Thus, the conventional apparatus not only has a complicated construction but also requires a wide installation space.
Meanwhile, U.S. Pat. No. 5,494,232 granted to Hirano et al. on Feb. 27, 1996 ("Hirano") discloses another apparatus for preventing reverse rotation of a spinning reel used for fishing.
Referring to FIG. 9, the apparatus for preventing reverse rotation disclosed in Hirano comprises a circular holder 109 rotatably mounted on a bushing, a circular external frame 110 rotatably fixed on a reel casting, and rolling members 107 retained by the circular holder 109 and the circular external frame 110. The circular holder 109 comprises a guide recess 108 for receiving the rolling members 107 therein. Each guide recess 108 has an open slot 108' at its lower portion, and the rolling members 107 received by the guide recess 108 through the open slot 108' is partially exposed to be contacted with the bushing. The rolling members 107 contact with the internal surface of the circular external frame 110 to function as a spiral. A spring 111 is provided inside the guide recess 108 to ease the rolling members 107 so as to function as a spiral.
According to the above construction, the spiral function of the rolling members 107 is generated by the internal circumference. Specifically, if the rolling members 107 are positioned at the concave portion 122 by means of the rectangular internal surfaces 121, 123 of the circular external frame 110, the bushing can freely rotate in clockwise and counterclockwise directions. However, if the rolling members 107 are positioned apart from the concave portion 122, reverse rotation of the bushing is prevented due to a frictional contact with the rolling members 107.
According to the above construction, one of the rolling members 107 is received between the two internal surfaces 121, 123 of the circular external frame 110. Thus, the internal surface of the circular external frame 110 is shaped octagonally. Considering the size of the apparatus as well as the rotation in both directions of the circular holder mounted on the spinning reel, it is practically impossible for the internal surface to have a geometrical shape which is more rectangular than octagonal. Accordingly, the number of rolling members is limited to four. In that case, if any of the rolling members 107 is damaged or the function of the spring for easing the rolling members deteriorates, the bushing is offset to that direction, thereby being unable to prevent reverse rotation of the bushing. Also, the apparatus for preventing reverse rotation as disclosed in the aforementioned patent has a complicated construction with numerous fittings, thereby increasing the manufacturing cost.